Electric heater



May 18 1926., 1,584,948

A.IJ'. KERCHER ET AL ELECTRI C HEATER Filed March*y 10. 1924 /NVs/vroes Patented ey, l, "i926,

ARTHUR J. KERCEEE, OF

BERKELEY, 4lfNlJ WXL'LEAVI WESLEY HICKS, 0F SAN FRANCISCO, CALIFORNIB..

minoren: Erlernen.

Application nled Haren 10,

This invention rehites to n device operated electrically, tor heating s space, such as n room or the like. More particularly, it relates to n heater in which the heat is imlinrted to thegspzice to oeheeted, by the aid ol' currents olf nir passing over surfaces lie-.ited electrically. Such e. convection 'type oi heater is disclosed for example in Aa copcnding application, tiled duly 17, 1922. in the nnnic of William Wesley Hicks, entitled Electric hector, und having Serial Number T5,543.

lt is one of the objects of the present invention to improve in ,general the heater shown in the seid copending cese.

1t is mother object ot the invention to increase, the ollicioncy oi such ai heater by providing e. compznntively long passogcwsy 'lor the nir in the heater, the better to 1nllucnce the oir :ind io impart n greater queniity olf heut thereto.

ln healers ot` this type, it is usual to provide heating elements comprising zi column olA refractory mutcriol, such as chiy, upon which one or more heating coils are placed. Sometimes the column is hollow, to provide n verliril passngc l'or the nir to be heated.

'l he. coils lnivc'usunlly been so arranged :1s to Le risible, und here been operated at some degree oi" incundescence so us to produce :n picirsing eilcct. llowever, it is well-known that it is more ellicient to oper-,ite the heater so thnlv no glow at nllis apparent. lt is i :u other object oiA our invention to provide ln tiling; units ol' such construction that-only :i minor port oi' the coils, forming the visible portions thereof., is oper-tied at the rclniivcly inollicient zglowing temperature.

1n the prior typespt' heaters referred to, the coils nrc supported in grooves located in ilieperiphery of the hollow member, there loing :is nniny independent grooves us there :ire coils. ln order to vary the intensity oi the heating, sometin'ies one or more ot' the coils vare entirely disconnected, leaving the others in :i glowing condition. 'lhis produces the effect of dark and glowing;f sections of the coils alternated in the grooves, und is Vsomewhat objectionable, since o more pleas- .ing effect is secured by having all of the exposed portions glowing. It is thus another' olqect of our invention to nnike 1t possible to expose only continuously glowing Wires 1924. sensi no. 69eme.

independently of variations in the degree of heat supplied by the heater.

Uur invention possesses other adventnf geous features, some of which 'with the oregoing will be set forth et length in the toln lowing description, where we shell outline/ in full that forno of the invention which we foo have selected for illustration in the drownogs accompanying and forming port olf/.the1 -present invention. Although we have in the drewings but one embodiment oi our invention, We do not desire to be limited thereto, since the invention es expressed `in the claims may he embodied in other forms also.

Referring to the drawiiws:

,Figure` 1 :is an elevation et" one of the heating elements, with some of theheeting wires omitted, in order to show the structure more clearly;

Fig. 2 is e sectional view, taken along plane 2-2 of Fig. 1, and showing bythe nid ot dotted lineshow the heating coils ere supported, end how the refractory supports are held in place;

Fig. 3 is :i sectional view, somewhat die giennnatic, of o, complete heater embodying our invention; and

Fig. 4t is a fragmentary cross sectional view ot the supportingicohunn for the wire rolls, und illustrates how the top ot the column is constructed.

In the diagrammatic 'View of Fig. 3, e recess `11 is indicated in the vertical wall ot :i rooin or space, which recess serves to eccoinmodute the heater. 1n order topermit the escape 4of onvectioncurrents of heated nir from the device, a front cover or grille 12 is used, having perforations over et least pnrt oi its surface for the intake und escupe ol oir 'l'roin behind .the grille 12.

ASupported on back of tlg/e grille 12. is u hcod or container 13 lievi/ng a vertical well :ind a horizontal shelf or extension 14 on which thehenting units 15 :ire supported. fit the top, the hood 13 curve.C over as shown :it 16 to meet the rear surface of grille 12. The heating elen'ient 15 vrcomprises in this instance,.i liollowfrectnngulur column ont retrirctory mterisl,-the faces of the column carrying helical coils arranged to he connected to a source of current. Theydetsils oit the units will he explainednt lengthin eonneetion Wilfrr "theother 'iffures on the drawing; for the present; is suileieut to nete that eool air may enter et bhe bottoni from helow 'the shellE il id pass through apertures in this shelf nto me hollow Space in the column, sind ou et; l mpinging againet the curved portion 16 ot the hood, land thereby delleeted. outwardly lroin the grille. i

A lortuous pase-:reentry is'however provvided .for the air hel'ore it; .is permitted to escape in the manner justoutlinetl, so that a. comparatively long period oi tune may elaprre heter(-A entry and exit, and a correspondingly lane amount of heat taken up. The intake el cool air i: effected near the bottoni oi' the'lifriile 1;. .horizontal pasi"'e\\'a\' l() ie' provided lhere'iior, 'formed in; thedtwo sheet nietul hoods Ill and 1S. These hoods are similar in forni to hood 13, hut olf progreeirelr larger size7 and each has n. horixontai portion il) or 2t), leading to Yertieal walls whivh curve ofer as l hown at 2l :1nd The. three hoods may he aptly Suid to he nested. lie outerxnmt hood 18 has its. eiirred portion :i2 fastened to the rear surl'aee ov e'i'ilie IY; .iut iheeurrixlportion 2l ot the intermediate hood stops short of the grille. and haaren :in open pahfaigtrwzxj/ 23 between the two pas v .wage formed hy i'i... three hooih. That: portion ot grille lli nhieh is oppoei're 'this eonneeting passageual 28 is,.iniperl`orae` so as to prevent an' i'ronl p; :zing outwardly at that point. The saine i -true of the rille near ihe bottoni hf tween the two horizontal ledges or Shelves -l und llj The. lahyrinthine pasrageway for the air trein .inletJ to outlet may now be. traced. ifroni the horizontal portion l0, the air travthe vertical pas.-:a{v\\'ay between the hood.' l? and iii; through the passageway ill); downward through the vertical pas sageway between the 'hoods 13 and 17; upwardlj)v through lhe heating elements lo, auf; iinailfY ont near the top of the grille t' eourse each ot' the hoede have side wullS nel ahown. .rhirh also attaeh to the rear :flirtare nl' the grille: and furthermore. it is to he |i1=der.--tm) t that as man); elements l5 may he flippin-'ml on the shelf 14 aS desired.

Due to the hiet, that. a long, tortuous path is travers-'wil h): the air in passing through the heater, ifean trike up e large amount of heut produced hy the element:

inipar heat to the Yaril5. '.l`lit\ .\eele1n ous passager lys hy radiation, eonreotion and Conduct on, and the air in turn is heated hy over ih'ese heated surfaces as well near the hoteonduetors formingr the :retire elements of units The eonstrueion oi? ihe heating; units l5 if; herrt diseloeed in, Figs. l, f2, and 4l. In plat-e, of an integral hollow tube \\ithhelial grooree to Support ehe heating eoils or near the top?.

we profele .in this instance Separated and greeted, vetieel Wells 25, which form side of e rectangular or square column. '011e advantage of such an. arrangement is that the coiled contini-'tors 2l may be Wound inde'pentlently around each of the walls as intleated in 'the dotted lines in 2; and in this wey, those Conductors which are wound on the wall facing the grille er cover i2 een he independently venergized to glowing temperature, while the oihers, which are not visible, can be more ellieiently energized below glowing temperature. Thus 'the pleazingleet. of glowing eondue tors .is retained without materiel departure from niaxiniuin operating elieiency.

A further advantage resides in the fact that the walls :25, which are moulded from retraetory material, such es clay, may manufactured without cores and Without any diilieulty whatsoever in removing the pattern. .lt is to noted that; those pol`- tions 01"' the grooves Q6 which are'on the poSed sides of the walls, are horizontal, the piteh eyeing teken up in the inner face, es indieated in dotied lines in Fig. l. Thiel improves 'the appearance ofthe heater when in operation. VFurthermore, the Wells in this instance are shown as provided with e. rontinuous groove,A forming the. equivalent of a single pitehetl Jitin-earl extending around the wall, and accommodating n.

eeiled conductor. However, if desired, a phirahl)v o't" grooves: may he used to form multiple threads. 'Only part oit' the concluetors indiealed in Fig. lhe remainder of the `grooves QG on all Walls being left nnoeeupied. The manner of insertion ol the remainder oi' the. Conductors iS eriflent, however, from the foregoing diseloenre.

rlhe ends el the eonduetors may lie appropriatelY anchored in any nimmer."

iThe manner of Supporting the Walls on the, shelf l-'lmay now be. described. QT are Stamped up 'from the shelf l-l to forni supports engaging the outside oi the walls Uf Course apertures 28 are lef 'in the shelfv 'of the shape of the clips, 'hieh apertures are disposed exterior of the column formed by the walls, but these' apertures are helpful in permitting the air to eseape Ytroni below i'ghe shelf 14 to the Space above it. ln somewhat; similar fashion, clips 29 enga@ ing the inner surfaces of the walls are stamped. out; of shelf 1l, in such manner that there is formed a rectangular aperture in this shelf. aline/d with the axis of the eohuim. ln Fig. 2, the dotted lines 30 and 31 illustrate how the shellPA is stamped before the clips 29 are bent up out of it to extend perpendieularly thereto, Appropriate feeteuing devices, such :1s the bolts and nutA 532, ma)v he provided for fasteningY the lower ende` ot' the walls E25 between the elips Q l and Q9. Furthermore, enough spacey is lel't Clips 

